A lava lake present within the Halema`uma`u Overlook vent during the past week resulted in night-time glow that was visible from the Jaggar Museum overlook. The lake, which is normally about 80–115 m (260–380 ft) below the floor of Halema`uma`u Crater and visible by HVO`s Webcam, rose and fell slightly during the week in response to a series of deflation-inflation cycles. A series of brief rise-fall cycles on April 14–15 brought the lava level to about 65 m (210 ft) below the floor of Halema`uma`u Crater.

On Kilauea`s east rift zone, surface lava flows were active on the pali and coastal plain in the Royal Gardens subdivision over the past week. As of Wednesday, April 18, the flows on the coastal plain were advancing towards the ocean but were still about 1.2 km (0.7 miles) from the water.

On the HVO website, a thermal image video of the high level of lava was posted. On April 14th, scientist said “several rise-fall cycles (short term increases in lava level immediately followed by spattering and an abrupt drop) pushed the level even higher over the past day. This Quicktime movie is a timelapse sequence taken from the Halemaʻumaʻu thermal camera, showing the rise-fall cycles and lava spilling out over the deep inner ledge during the high stands. For scale, the inner ledge is about 70 m (about 230 ft) below the vent rim. Also, note the “bathtub ring” left by the high stands after the lava level drops.”